Tryptophanyl tRNA synthetase (TrpRS) is one of the crucial enzymes that participates in protein synthesis. The structural study of TrpRS (from Bucillus stearothermophilus) may not only illuminate understanding of the fundamental biochemistry of protein synthesis, but also provide a basis for rational drug design (e.g. antibiotic indolmycin). We have begun working with Dr. Carter and his student Yuhui Yin on the refinement of their model for the structure of this protein.